Method for controlling a disc motor

Abstract

The application is applied to the technical field of motor control, and discloses a method for controlling a disc motor. The method comprises the following steps: obtaining current information and voltage information of a stator winding of a disc motor to be monitored, current response information corresponding to the stator winding, bus voltage, temperature information and three-phase current of the stator winding of the disc motor to be monitored; obtaining the demagnetization degree of each subzone in the disc motor to be monitored according to the current response information; obtaining the flux linkage state of a permanent magnet of each subzone in the disc motor to be monitored according to the current information and the voltage information; obtaining the real-time temperature field and the real-time electromagnetic field of each subzone in the disc motor to be monitored according to the bus voltage, the temperature information and the three-phase current of the stator winding; and controlling the disc motor to be monitored according to the demagnetization degree of each subzone, the flux linkage state of the permanent magnet of each subzone, the temperature field and the electromagnetic field. In this way, the accurate monitoring and control of local problems of the disc motor are realized.

Description

Technical Field

[0001] This invention relates to the field of motor control technology, and more specifically to a method for controlling a disc motor. Background Technology

[0002] Currently, disc motors, with their advantages of compact structure, high power density, small axial dimensions, and high torque density, are widely used in many fields such as new energy vehicles, industrial transmissions, aerospace equipment, and rail transportation. The permanent magnets in disc motors with axial flux structures are mostly distributed in a ring array. Due to the special flat structure of disc motors, the multi-zone arrangement of permanent magnets, and the long-term influence of variable operating conditions, problems such as localized demagnetization of permanent magnets, abnormal magnetic flux linkage, and uneven distribution of temperature and electromagnetic fields can easily occur inside the motor.

[0003] Current technologies only monitor and control the permanent magnets of a disc motor as a whole. However, due to uneven heat dissipation and stress distribution, the health status of permanent magnets in different zones varies, and the states of permanent magnets in each zone are also different. Overall monitoring and control cannot accurately perceive and regulate the local conditions of permanent magnets, which leads to the amplification of local problems and affects the normal operation of the disc motor.

[0004] Therefore, in order to overcome the above-mentioned technical problems, the present invention provides a method for controlling a disc motor. Summary of the Invention

[0005] The technical problem to be solved by the present invention is how to achieve accurate monitoring and control of local problems of disc motors. The purpose is to provide a method for controlling disc motors so as to achieve accurate monitoring and control of local problems of disc motors.

[0006] This invention is achieved through the following technical solution:

[0007] In a first aspect, a method for controlling a disc motor is provided, the method comprising: acquiring current and voltage information of the stator winding of the disc motor under monitoring during operation; acquiring current response information corresponding to the stator winding; acquiring bus voltage, temperature information, and three-phase current of the stator winding of the disc motor under monitoring; acquiring the demagnetization degree of each section of the disc motor under monitoring based on the current response information; acquiring the flux linkage state of the permanent magnets in each section of the disc motor under monitoring based on the current and voltage information; acquiring the real-time temperature field and real-time electromagnetic field of each section of the disc motor under monitoring based on the bus voltage, temperature information, and three-phase current of the stator winding; and controlling the disc motor under monitoring based on the demagnetization degree of each section, the flux linkage state of the permanent magnets in each section, the temperature field, and the electromagnetic field.

[0008] In some embodiments, the stator winding is connected to an inverter and a current sensor; obtaining the current response information corresponding to the stator winding includes: when the disc motor to be monitored is running, inputting a preset excitation signal to the stator winding through the inverter; then collecting the response current output by the stator winding in response to the excitation signal through the current sensor; and determining the response current as the current response information.

[0009] In some embodiments, obtaining the demagnetization degree of each partition in the disc motor to be monitored based on the current response information includes: performing wavelet packet decomposition on the current response information to obtain several decomposed response components; obtaining high-frequency response components from each of the decomposed response components; inputting the high-frequency response components into a preset inductance feature extraction model to obtain direct-axis inductance feature data corresponding to each partition of the permanent magnet; and determining the demagnetization degree of each partition based on each of the direct-axis inductance data.

[0010] In some embodiments, determining the demagnetization degree of each partition based on the direct-axis inductance data includes: performing a search operation using a preset inductance demagnetization database to obtain the demagnetization degree of each partition and the inductance range corresponding to the demagnetization degree; for each partition, determining the inductance range of its corresponding direct-axis inductance characteristic data; and determining the demagnetization degree corresponding to the inductance range as the demagnetization degree of that partition.

[0011] In some embodiments, obtaining the flux linkage state of the permanent magnets in each partition of the disc motor to be monitored based on the current information and the voltage information includes: extracting the fundamental current wave and the lower harmonic current wave of the current signal; extracting the fundamental voltage wave and the lower harmonic voltage wave of the voltage signal; obtaining the back electromotive force time-domain waveform of the disc motor to be monitored based on the fundamental current wave, the lower harmonic current wave, the fundamental voltage wave, and the lower harmonic voltage wave; extracting the distortion features corresponding to the back electromotive force time-domain waveform; obtaining the waveform data corresponding to the back electromotive force time-domain waveform; inputting the waveform data and the distortion features into a preset flux linkage feature extraction model to obtain the flux linkage feature value of each partition; and determining the flux linkage state of each partition based on the flux linkage feature value.

[0012] In some embodiments, determining the state of each magnetic flux linkage based on each magnetic flux linkage feature value includes: performing a lookup operation on each magnetic flux linkage feature value using a preset magnetic flux linkage state database to obtain the magnetic flux linkage state corresponding to each magnetic flux linkage feature value; the preset magnetic flux linkage state database stores the correspondence between each magnetic flux linkage feature value and each magnetic flux linkage state; and determining the magnetic flux linkage state corresponding to each magnetic flux linkage feature value as the magnetic flux linkage state of the permanent magnet in each partition.

[0013] In some embodiments, obtaining the real-time temperature field and real-time electromagnetic field of each zone in the disc motor to be monitored based on the bus voltage, temperature information, and the three-phase current of the stator winding includes: constructing a digital twin model of the disc motor to be monitored; inputting the bus voltage, temperature information, and the three-phase current of the stator winding into the digital twin model to obtain a candidate motor simulation model; performing real-time correction on the candidate motor simulation model based on the current information and the voltage information to obtain a motor simulation model; obtaining the simulated temperature field and simulated electromagnetic field of each zone in the motor simulation model; determining the simulated temperature field of each zone as the real-time temperature field of each zone; and determining the simulated electromagnetic field of each zone as the real-time electromagnetic field of each zone.

[0014] In some embodiments, controlling the disc motor to be monitored based on the demagnetization degree of each partition, the flux linkage state of the permanent magnets in each partition, the temperature field, and the electromagnetic field includes: performing magnetic field compensation based on the demagnetization degree of each partition; adjusting the operating point and current distribution of the disc motor to be monitored based on the temperature field; determining the demagnetization trend of the permanent magnets in each partition based on the demagnetization degree of each partition, the flux linkage state of the permanent magnets in each partition, the real-time temperature field, and the real-time electromagnetic field; and controlling the disc motor to be monitored to switch to a preset conservative control mode when the demagnetization trend indicates an accelerating demagnetization trend.

[0015] In some embodiments, the magnetic field compensation based on the demagnetization degree of each partition includes: locating the partition that needs compensation based on the demagnetization degree of each partition; determining the compensation harmonic current based on the partition that needs compensation and the demagnetization degree of the partition; and injecting the compensation harmonic current into the stator winding corresponding to the partition that needs compensation to perform magnetic field compensation for the partition that needs compensation.

[0016] In some embodiments, determining the compensation harmonic current based on the zone to be compensated and the degree of demagnetization of the zone to be compensated includes: performing a lookup operation in a preset current parameter database based on the zone to be compensated and the degree of demagnetization of the zone to be compensated to obtain the phase parameter and amplitude parameter of the compensation harmonic current; the current parameter database stores the correspondence between the zone, the degree of demagnetization, and the phase parameter and amplitude parameter; determining the compensation harmonic current based on the phase parameter and amplitude parameter; the compensation harmonic current is a sinusoidal current.

[0017] Compared with existing technologies, this invention acquires the current, voltage, and current response information of the stator windings, the bus voltage and temperature information of the disc motor under monitoring, and the three-phase current of the stator windings during operation. Then, based on the current response information, it obtains the demagnetization degree of each section of the disc motor under monitoring; based on the current and voltage information, it obtains the flux linkage state of the permanent magnets in each section of the disc motor under monitoring; based on the bus voltage, temperature information, and the three-phase current of the stator windings, it obtains the real-time temperature field and real-time electromagnetic field of each section of the disc motor under monitoring; and finally, it controls the disc motor under monitoring based on the demagnetization degree of each section, the flux linkage state of the permanent magnets in each section, the temperature field, and the electromagnetic field. In this way, compared with the existing technology, the demagnetization degree, flux linkage state, real-time temperature field and real-time electromagnetic field of each zone in the disc motor under test are realized by using current response information, current information, voltage information, bus voltage, temperature information and three-phase current of stator winding. Based on the monitoring results, the disc motor under test is controlled, making the control more targeted and realizing the accurate monitoring and control of local problems of the disc motor. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0019] Figure 1 This is a flowchart illustrating a method for controlling a disc motor provided by the present invention;

[0020] Figure 2 This is a schematic diagram of a device for controlling a disc motor provided by the present invention;

[0021] Figure 3 This is a schematic diagram of another device for controlling a disc motor provided by the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0023] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention as detailed in the appended claims.

[0024] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0025] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0026] In this invention, "multiple" refers to two or more. "And / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following associated objects have an "or" relationship.

[0027] It should be noted that the disc motor to be monitored has multiple partitions, and each partition is equipped with a permanent magnet and a stator winding.

[0028] Please see Figure 1 , Figure 1 This is a schematic flowchart illustrating a method for controlling a disc motor, as shown in an exemplary embodiment of the present invention. Figure 1 Some steps in the process can be arbitrarily combined, and / or the order of some operations can be arbitrarily changed.

[0029] like Figure 1 As shown, the method for controlling a disc motor includes:

[0030] Step S101: Obtain the current and voltage information of the stator winding of the disc motor under monitoring during operation; obtain the current response information of the stator winding; obtain the bus voltage, temperature information and three-phase current of the stator winding of the disc motor under monitoring.

[0031] Step S102: Obtain the demagnetization degree of each zone in the disc motor to be monitored based on the current response information.

[0032] Step S103: Obtain the flux linkage state of the permanent magnets in each section of the disc motor to be monitored based on the current and voltage information.

[0033] Step S104: Obtain the real-time temperature field and real-time electromagnetic field of each zone in the disc motor to be monitored based on the bus voltage, temperature information and the three-phase current of the stator winding.

[0034] Step S105: Control the disc motor to be monitored based on the demagnetization degree of each zone, the flux linkage state of the permanent magnets in each zone, the temperature field, and the electromagnetic field.

[0035] In this embodiment, the current, voltage, and current response information of the stator windings, as well as the bus voltage, temperature, and three-phase current of the stator windings of the disc motor under monitoring are acquired during operation. Then, based on the current response information, the demagnetization degree of each section of the disc motor is obtained; based on the current and voltage information, the flux linkage state of the permanent magnets in each section is obtained; and based on the bus voltage, temperature, and three-phase current of the stator windings, the real-time temperature and electromagnetic fields of each section are obtained. Finally, the disc motor is controlled based on the demagnetization degree, flux linkage state of the permanent magnets in each section, temperature field, and electromagnetic field. Compared to existing technologies, this method achieves real-time monitoring of the demagnetization degree, flux linkage state, real-time temperature field, and real-time electromagnetic field of each section of the disc motor using current response information, current information, voltage information, bus voltage, temperature, and three-phase current of the stator windings. Controlling the disc motor based on the monitoring results makes the control more targeted and achieves precise monitoring and control of localized problems in the disc motor.

[0036] At the same time, it enables intelligent and precise control of motor operation, making it suitable for high-reliability scenarios such as aerospace and electric vehicles.

[0037] It should be noted that the stator windings are all connected to an inverter, a current sensor, and a voltage sensor.

[0038] Both the current sensor and the voltage sensor are high-bandwidth sensors.

[0039] It should be noted that the high-bandwidth characterization sensor can simultaneously capture rapidly changing electrical signals such as DC, power frequency, high-frequency harmonics, pulses, transient spikes, and switching transients, without amplitude attenuation, phase lag, or waveform distortion, thus achieving accurate measurement of current or voltage.

[0040] It should be noted that the current sensor can be a three-phase current sensor, capable of measuring the three-phase current of the stator winding. The current information of the stator winding can be the current information of any one of the three phases.

[0041] The inverter is connected to the input terminal of the stator winding.

[0042] The current information includes the current of a preset phase from the three-phase currents of each stator winding collected by each current sensor. The preset phase can be phase a, phase b, or phase c.

[0043] The voltage information includes the voltage across each stator winding collected by each voltage sensor.

[0044] It should be noted that when collecting current and voltage information, it is not necessary to input a preset excitation signal to the stator winding.

[0045] Furthermore, in Figure 1 In step S101, obtaining the current response information corresponding to the stator winding includes: when the disc motor to be monitored is running, inputting a preset excitation signal to the stator winding through the inverter; then obtaining the response current output by the stator winding in response to the excitation signal through the current sensor; and determining the response current as the current response information.

[0046] In this way, when the disc motor under monitoring is running, a preset excitation signal is input to the stator winding through the inverter. Without stopping the machine, a response current that conforms to the normal operating conditions of the disc motor under monitoring can be obtained. Then, the response current is determined as current response information, so as to determine the degree of demagnetization based on the current response information.

[0047] It should be noted that since each zone corresponds to one stator winding, the current response information includes the response current of the stator winding corresponding to each zone in response to the excitation signal output. Specifically, this response current can be the current of any one phase of the three-phase current collected by the current sensor after the preset excitation signal is input.

[0048] It should be noted that the excitation signal is a high-frequency, low-amplitude voltage or current signal.

[0049] In some embodiments, when the excitation signal is a voltage signal, its amplitude can be 1% to 3% of the rated voltage of the disc motor; when the excitation signal is a current signal, its amplitude can be 2% to 5% of the rated current of the disc motor.

[0050] In this way, the excitation signal causes minimal disturbance to the stator windings, does not change the fundamental operating state of the motor, and does not affect the normal torque output of the motor.

[0051] Furthermore, in Figure 1In step S102, the demagnetization degree of each zone in the disc motor to be monitored is obtained based on the current response information, including: performing wavelet packet decomposition on the current response information to obtain several decomposed response components; obtaining high-frequency response components from each decomposed response component; inputting the high-frequency response components into a preset inductance feature extraction model to obtain direct-axis inductance feature data corresponding to each zone of the permanent magnet; and determining the demagnetization degree of each zone based on each direct-axis inductance data.

[0052] Thus, since the strength of the permanent magnet changes the magnetic reluctance of the motor's magnetic circuit and the equivalent inductance of the windings, and this equivalent inductance directly determines the current response characteristics of the stator windings under the excitation signal, these current response characteristics can reflect the strength of the permanent magnet's magnetism. Simultaneously, since the current response information includes the response current of the stator windings corresponding to each zone in response to the excitation signal output, it contains the current response characteristics of the permanent magnets in each zone, reflecting the strength of the permanent magnets in each zone and thus indicating the degree of demagnetization. This scheme obtains several decomposed response components by performing wavelet packet decomposition on the current response information; high-frequency response components are extracted from each decomposed response component to extract the current response characteristics; then, the high-frequency response components are input into a preset inductance feature extraction model to obtain the direct-axis inductance feature data corresponding to each zone of the permanent magnet; based on each direct-axis inductance data, the degree of demagnetization in each zone is determined, achieving accurate calculation of the degree of demagnetization in each zone.

[0053] It should be noted that wavelet packet decomposition of the current response information can be performed using the db4 wavelet basis and a 3-level decomposition. Other wavelet bases and decomposition levels can also be set; there are no restrictions here.

[0054] Wavelet packet decomposition can decompose the current response information into several decomposed response components corresponding to preset frequencies.

[0055] It should be noted that the high-frequency response components obtained from each decomposed response component are decomposed response components with the same frequency as the excitation signal.

[0056] In some embodiments, since the disc motor is also operating normally when the current sensor collects the current response information, the current response information also contains the fundamental wave information output by the stator winding during normal operation of the disc motor. Wavelet packet decomposition can separate the fundamental wave information from the high-frequency response component that the stator winding actually responds to the excitation signal, thereby accurately extracting the high-frequency response component.

[0057] It should be noted that the inductance feature extraction model can be a deep neural network.

[0058] In some embodiments, the inductance feature extraction model may include an input layer, multiple hidden layers, a Dropout layer corresponding to each hidden layer, and an output layer.

[0059] Specifically, the input layer is used to input high-frequency response components. The hidden layer can consist of three layers. Each hidden layer is configured with neurons and a preset activation function, such as ReLU. The first hidden layer extracts the basic features of the current amplitude, phase, and waveform of the high-frequency response components. The second hidden layer fuses deep temporal features from the basic features of current amplitude, phase, and waveform. The third hidden layer compresses the fused features. The Dropout layer randomly sets the output of some neurons in its corresponding hidden layer to 0, thereby reducing co-adaptation between neurons and improving the model's generalization ability. The output layer performs a linear mapping on the compressed features to obtain the direct-axis inductance feature data corresponding to each partition of the permanent magnet.

[0060] During training, the inductance feature extraction model can be trained by measuring the actual d-axis inductance value of each partition using standard electromagnetic detection equipment and combining it with the training high-frequency response components as samples.

[0061] Furthermore, based on the direct-axis inductance data, the degree of demagnetization of each partition is determined, including: performing a search operation using a preset inductance demagnetization database to obtain the degree of demagnetization of each partition and the inductance range corresponding to the degree of demagnetization; for each partition, determining the inductance range of its corresponding direct-axis inductance characteristic data; and determining the degree of demagnetization corresponding to the inductance range as the degree of demagnetization of that partition.

[0062] Furthermore, in Figure 1 In step S103, the flux linkage state of the permanent magnets in each zone of the disc motor to be monitored is obtained based on the current and voltage information, including: extracting the fundamental current wave and low harmonic current wave of the current signal; extracting the fundamental voltage wave and low harmonic voltage wave of the voltage signal; obtaining the back electromotive force time-domain waveform of the disc motor to be monitored based on the fundamental current wave, low harmonic current wave, fundamental voltage wave, and low harmonic voltage wave; extracting the distortion features corresponding to the back electromotive force time-domain waveform; obtaining the waveform data corresponding to the back electromotive force time-domain waveform; inputting the waveform data and distortion features into a preset flux linkage feature extraction model to obtain the flux linkage feature value of each zone; and determining the flux linkage state based on each flux linkage feature value.

[0063] Thus, since the back electromotive force is strongly correlated with the flux linkage of the permanent magnet, this scheme extracts the fundamental current wave and low-order harmonics of the current signal, as well as the fundamental voltage wave and low-order harmonics of the voltage signal. Then, based on the fundamental current wave, low-order harmonics of the current, fundamental voltage wave, and low-order harmonics of the voltage, the time-domain waveform of the back electromotive force strongly correlated with the flux linkage of the permanent magnet in the disc motor to be monitored is obtained. The distortion characteristics and waveform data corresponding to the time-domain waveform of the back electromotive force are then extracted and input into the preset flux linkage feature extraction model to obtain the flux linkage feature values ​​of each partition, thereby determining the flux linkage state of each partition and achieving accurate judgment of the flux linkage state of each partition.

[0064] It should be noted that extracting the fundamental current and lower harmonics of the current signal involves performing Fourier decomposition on the current signal to obtain the fundamental current and lower harmonics.

[0065] Similarly, the fundamental voltage wave and lower harmonics of the voltage signal can be extracted by performing Fourier decomposition on the voltage signal to obtain the fundamental voltage wave and lower harmonics.

[0066] Furthermore, the time-domain waveform of the back electromotive force of the disc motor under monitoring is obtained based on the fundamental current, lower harmonic current, fundamental voltage, and lower harmonic voltage, including: for the nth order, by calculation This yields the back electromotive force waveform of the nth order. This represents the back electromotive force waveform of the nth order. This represents the voltage waveform of order n; specifically, when n is 0, It is the fundamental voltage frequency; when n is greater than 0, This refers to the nth order lower harmonic of the voltage; n is an integer greater than or equal to 0. This is the phase resistance of the stator winding, which is the rated value; This represents the current waveform of order n; specifically, when n is 0, It is the fundamental current wave; when n is greater than 0, It represents the nth order low-order harmonic of the current. Let be the phase inductance of the stator winding, which is the calibrated value. The back EMF waveforms of each order are summed to obtain the back EMF time-domain waveform.

[0067] Furthermore, the distortion features corresponding to the back EMF time-domain waveform are extracted, including: extracting the peak sequence, valley sequence, peak-to-peak sequence, flat-top defect sequence, and concave defect sequence of the back EMF time-domain waveform.

[0068] It should be noted that the elements of the peak sequence include the peak values ​​of each peak in the back EMF time-domain waveform.

[0069] The elements of the valley sequence include the valley values ​​of each valley in the back electromotive force time-domain waveform.

[0070] The elements of the peak-to-peak sequence include the difference between the peak and the next adjacent trough in the back EMF time-domain waveform.

[0071] The a-th element in the flat-top defect sequence is an index value representing whether the a-th wave in the back electromotive force time-domain waveform is a flat-top defect.

[0072] The a-th element in the concave defect sequence is an index value representing whether the a-th wave in the back electromotive force time-domain waveform is a concave defect.

[0073] It should be noted that obtaining the waveform data corresponding to the back EMF time-domain waveform involves sampling the back EMF time-domain waveform; then, the sampled values ​​are arranged in order in the back EMF time-domain waveform to obtain the waveform data corresponding to the back EMF time-domain waveform.

[0074] Furthermore, the waveform data and distortion features are input into a preset flux linkage feature extraction model to obtain flux linkage feature values ​​for each partition, including: splicing waveform data and distortion features to obtain input features; inputting the input features into the preset flux linkage feature extraction model to obtain flux linkage feature values ​​for each partition.

[0075] In some embodiments, the magnetic flux linkage feature extraction model can be an LSTM (Long Short-Term Memory) model.

[0076] Specifically, the magnetic linkage feature extraction model includes an input layer, a hidden layer, and an output layer.

[0077] The input layer is used to input this input feature.

[0078] The hidden layer comprises multiple LSTM units. During training, it learns the temporal relationship between the training input vector and the training labels, constructing a non-linear mapping between them. The training input vector is the input vector used during training; the training labels are the training flux linkage feature values ​​of each partition corresponding to the input vector used during training. After training, the flux linkage feature values ​​of each partition corresponding to the input features are determined based on this non-linear mapping.

[0079] The output layer is used to output the flux linkage characteristic values ​​of each partition.

[0080] Furthermore, the state of each flux linkage is determined based on its characteristic values, including: performing a lookup operation on each characteristic value using a pre-defined flux linkage state database to obtain the flux linkage state corresponding to each characteristic value. The flux linkage states corresponding to each characteristic value are then determined as the flux linkage states of the permanent magnets in each partition. The pre-defined flux linkage state database stores the correspondence between each characteristic value and each flux linkage state.

[0081] In some embodiments, the flux linkage state can include: undecayed and decayed. The flux linkage characteristic value corresponding to the undecayed state is 0; the flux linkage characteristic value corresponding to the decayed state is 1. Other flux linkage states and characteristic values ​​can also be set, and are not limited here.

[0082] Furthermore, in Figure 1In step S104, the real-time temperature field and real-time electromagnetic field of each zone in the disc motor to be monitored are obtained based on the bus voltage, temperature information, and three-phase current of the stator winding. This includes: constructing a digital twin model of the disc motor to be monitored; inputting the bus voltage, temperature information, and three-phase current of the stator winding into the digital twin model to obtain a candidate motor simulation model; performing real-time correction on the candidate motor simulation model based on the current and voltage information to obtain a motor simulation model; obtaining the simulation temperature field and simulation electromagnetic field of each zone in the motor simulation model; determining the simulation temperature field of each zone as the real-time temperature field of each zone; and determining the simulation electromagnetic field of each zone as the real-time electromagnetic field of each zone.

[0083] In this way, by constructing a digital twin model of the disc motor to be monitored, and then inputting the bus voltage, temperature information, and three-phase current of the stator winding into the digital twin model, a candidate motor simulation model is obtained. Based on the current and voltage information, the candidate motor simulation model is then corrected in real time to obtain the final motor simulation model. The simulated temperature field and simulated electromagnetic field of each zone in the motor simulation model are then obtained. The simulated temperature field of each zone is determined as the real-time temperature field of that zone, and the simulated electromagnetic field of each zone is determined as the real-time electromagnetic field of that zone. Using the corrected simulated temperature field and simulated electromagnetic field of the motor simulation model to determine the real-time temperature field and real-time electromagnetic field, compared to discrete sensor sampling, yields data with richer dimensions and stronger spatial continuity. This facilitates the accurate capture of subtle anomalies such as local temperature rise and magnetic field distortion, improving the monitoring accuracy and real-time performance of the disc motor.

[0084] Furthermore, the candidate motor simulation model is calibrated in real time based on current and voltage information to obtain the motor simulation model. This includes extracting the simulated current and resistance information of the stator winding from the candidate motor simulation model. A preset Kalman filter algorithm or neural network model is used to calibrate the candidate motor simulation model in real time based on the simulated current and resistance information to obtain the motor simulation model.

[0085] This reduces the deviation between the model and actual working conditions, and improves monitoring accuracy.

[0086] Specifically, Kalman filtering algorithms or neural network models can be used to determine the parameters of the candidate motor simulation model based on the simulated current and resistance information. For example, one or more parameters such as stator resistance, direct-axis and quadrature-axis inductance, flux linkage, moment of inertia, and damping coefficient can be used to configure the candidate motor simulation model and achieve its calibration.

[0087] Furthermore, in Figure 1In step S105, the monitored disc motor is controlled according to the demagnetization degree of each zone, the flux linkage state of the permanent magnets in each zone, the temperature field, and the electromagnetic field. This includes: performing magnetic field compensation according to the demagnetization degree of each zone; adjusting the operating point and current distribution of the monitored disc motor according to the temperature field; determining the demagnetization trend of the permanent magnets in each zone according to the demagnetization degree of each zone, the flux linkage state of the permanent magnets in each zone, the real-time temperature field, and the real-time electromagnetic field; and controlling the monitored disc motor to switch to a preset conservative control mode when the demagnetization trend indicates an accelerating demagnetization trend.

[0088] In this way, by compensating for the magnetic field based on the demagnetization degree of each zone, and adjusting the operating point and current distribution of the monitored disc motor according to the temperature field, the demagnetization trend of the permanent magnets in each zone is determined based on the demagnetization degree, the flux linkage state of the permanent magnets in each zone, the real-time temperature field, and the real-time electromagnetic field. Then, when the demagnetization trend indicates an accelerating demagnetization trend, the monitored disc motor is switched to a preset conservative control mode. This forms a multi-level control system encompassing magnetic field compensation, thermal safety regulation, fault prediction, and fault-tolerant protection. It provides targeted control for abnormal conditions of the monitored disc motor to mitigate problems and achieve high reliability, high efficiency, and stable operation. Simultaneously, by switching to a conservative control strategy, the monitored disc motor can be prevented from shutting down due to sudden faults, thus improving its reliability.

[0089] Furthermore, magnetic field compensation is performed based on the degree of demagnetization of each zone, including: locating the zone that needs compensation based on the degree of demagnetization of each zone; determining the compensation harmonic current based on the zone that needs compensation and its degree of demagnetization; and injecting the compensation harmonic current into the stator winding corresponding to the zone that needs compensation to perform magnetic field compensation for the zone that needs compensation.

[0090] It should be noted that the degree of demagnetization can include no demagnetization, slight demagnetization, and severe demagnetization. The partitions requiring compensation are identified based on their degree of demagnetization; that is, partitions with slight or severe demagnetization are determined as those requiring compensation.

[0091] It should be noted that determining the compensating harmonic current based on the zone requiring compensation and its demagnetization degree includes: performing a lookup operation in a preset current parameter database according to the zone requiring compensation and its demagnetization degree to obtain the phase and amplitude parameters of the compensating harmonic current. The compensating harmonic current is then determined based on these phase and amplitude parameters. The current parameter database stores the correspondence between the zone, demagnetization degree, phase parameters, and amplitude parameters. In some embodiments, the compensating harmonic current can be a sinusoidal current.

[0092] In this way, by injecting compensating harmonic current, the magnetic field deficiency in the demagnetizing region is precisely offset, thereby suppressing the torque pulsation caused by the magnetic field deficiency and ensuring the stable operation of the disc motor under monitoring.

[0093] It should be noted that the operating point and current distribution of the disc motor under monitoring are adjusted according to the real-time temperature field. That is, when the temperature in the real-time temperature field is greater than the preset temperature threshold, the operating point and current distribution of the disc motor under monitoring are adjusted to reduce the temperature of the disc motor under monitoring.

[0094] Specifically, the operating point may include the peak power point and torque parameter point of the disc motor to be monitored. In some embodiments, if the temperature in the temperature field is greater than a preset temperature threshold, the peak power point and torque parameter point can be reduced.

[0095] The current distribution refers to the distribution of the direct-axis current and quadrature-axis current of the disc motor to be monitored.

[0096] In this way, by adjusting the operating point and distribution current of the disc motor under monitoring, the temperature of the permanent magnet can be controlled within a safe range without affecting the basic operating performance of the disc motor under monitoring, thus preventing permanent demagnetization caused by high temperature and achieving a synergistic balance between thermal safety and operating efficiency.

[0097] It should be noted that when the demagnetization trend indicates an accelerating demagnetization trend, the monitored disc motor is switched to a preset conservative control mode. This includes: directly switching the monitored disc motor to the preset conservative control mode when the demagnetization trend indicates an accelerating demagnetization trend; or predicting the remaining lifespan of the monitored disc motor when the demagnetization trend indicates an accelerating demagnetization trend; and switching the monitored disc motor to the preset conservative control mode when the remaining lifespan is less than a preset lifespan alarm threshold.

[0098] It should be noted that existing lifespan prediction methods can be used to predict the remaining lifespan of the monitored disc motor, and no restrictions are imposed here. The conservative control mode smoothly adjusts the power of the monitored disc motor to a preset healthy power range to achieve fault-tolerant operation and avoid sudden shutdowns.

[0099] Combination Figure 2 As shown, the present invention provides a device 200 for controlling a disc motor, the device comprising: a data acquisition module 201, a first acquisition module 202, a second acquisition module 203, a third acquisition module 204, and a control module 205.

[0100] The data acquisition module 201 is configured to acquire the current and voltage information of the stator winding of the disc motor under monitoring during operation; acquire the current response information of the stator winding; and acquire the bus voltage, temperature information, and three-phase current of the stator winding of the disc motor under monitoring.

[0101] The first acquisition module 202 is configured to acquire the demagnetization degree of each partition in the disc motor to be monitored based on the current response information.

[0102] The second acquisition module 203 is configured to acquire the flux linkage state of the permanent magnets in each partition of the disc motor to be monitored based on current information and voltage information.

[0103] The third acquisition module 204 is configured to acquire the real-time temperature field and real-time electromagnetic field of each zone in the disc motor to be monitored based on the bus voltage, temperature information and the three-phase current of the stator winding.

[0104] The control module 205 is configured to control the disc motor to be monitored based on the demagnetization degree of each zone, the flux linkage state of the permanent magnets in each zone, the temperature field, and the electromagnetic field.

[0105] The device for controlling a disc motor provided by this invention acquires the current, voltage, and current response information of the stator windings, the bus voltage and temperature information of the disc motor under monitoring, and the three-phase current of the stator windings during operation. Then, based on the current response information, the demagnetization degree of each section of the disc motor under monitoring is obtained; based on the current and voltage information, the flux linkage state of the permanent magnets in each section of the disc motor under monitoring is obtained; based on the bus voltage, temperature information, and the three-phase current of the stator windings, the real-time temperature field and real-time electromagnetic field of each section of the disc motor under monitoring are obtained; and finally, the disc motor under monitoring is controlled based on the demagnetization degree of each section, the flux linkage state of the permanent magnets in each section, the temperature field, and the electromagnetic field. In this way, compared with the existing technology, the demagnetization degree, flux linkage state, real-time temperature field and real-time electromagnetic field of each zone in the disc motor under test are realized by using current response information, current information, voltage information, bus voltage, temperature information and three-phase current of stator winding. Based on the monitoring results, the disc motor under test is controlled, making the control more targeted and realizing the accurate monitoring and control of local problems of the disc motor.

[0106] Furthermore, the stator windings are connected to an inverter and a current sensor; Figure 2 The data acquisition module is configured to acquire the current response information of the stator winding in the following way: when the disc motor to be monitored is running, a preset excitation signal is input to the stator winding through the inverter; then the response current of the stator winding in response to the excitation signal is acquired through the current sensor; and the response current is determined as the current response information.

[0107] Furthermore, Figure 2 The first acquisition module is configured to acquire the demagnetization degree of each partition in the disc motor to be monitored based on the current response information in the following manner: perform wavelet packet decomposition on the current response information to obtain several decomposed response components; obtain high-frequency response components from each decomposed response component; input the high-frequency response components into a preset inductance feature extraction model to obtain the direct-axis inductance feature data corresponding to each partition of the permanent magnet; and determine the demagnetization degree of each partition based on each direct-axis inductance data.

[0108] Furthermore, Figure 2 The second acquisition module is configured to acquire the flux linkage state of the permanent magnets in each zone of the disc motor to be monitored based on current and voltage information in the following manner: extracting the fundamental current wave and low harmonic current wave of the current signal; extracting the fundamental voltage wave and low harmonic voltage wave of the voltage signal; acquiring the back electromotive force time-domain waveform of the disc motor to be monitored based on the fundamental current wave, low harmonic current wave, fundamental voltage wave, and low harmonic voltage wave; extracting the distortion features corresponding to the back electromotive force time-domain waveform; acquiring the waveform data corresponding to the back electromotive force time-domain waveform; inputting the waveform data and distortion features into a preset flux linkage feature extraction model to obtain the flux linkage feature value of each zone; and determining the flux linkage state based on each flux linkage feature value.

[0109] Furthermore, Figure 2 The third acquisition module is configured to acquire the real-time temperature field and real-time electromagnetic field of each zone in the disc motor to be monitored based on the bus voltage, temperature information, and three-phase current of the stator winding in the following manner: constructing a digital twin model of the disc motor to be monitored; inputting the bus voltage, temperature information, and three-phase current of the stator winding into the digital twin model of the motor to obtain a candidate motor simulation model; performing real-time correction on the candidate motor simulation model based on the current information and voltage information to obtain a motor simulation model; acquiring the simulation temperature field and simulation electromagnetic field of each zone in the motor simulation model; determining the simulation temperature field of each zone as the real-time temperature field of each zone; and determining the simulation electromagnetic field of each zone as the real-time electromagnetic field of each zone.

[0110] Furthermore, Figure 2 The control module is configured to control the monitored disc motor in the following ways based on the demagnetization degree of each zone, the flux linkage state of the permanent magnets in each zone, the temperature field, and the electromagnetic field: perform magnetic field compensation based on the demagnetization degree of each zone; adjust the operating point and current distribution of the monitored disc motor based on the temperature field; determine the demagnetization trend of the permanent magnets in each zone based on the demagnetization degree of each zone, the flux linkage state of the permanent magnets in each zone, the real-time temperature field, and the real-time electromagnetic field; and control the monitored disc motor to switch to a preset conservative control mode when the demagnetization trend indicates an accelerating demagnetization trend.

[0111] It should be noted that the device for controlling the disc motor includes a data acquisition layer, a fusion monitoring layer, and a control layer. The data acquisition layer includes a data acquisition module for acquiring current information, voltage information, current response information, bus voltage, temperature information, and the three-phase current of the stator winding. The fusion monitoring layer includes a first acquisition module, a second acquisition module, and a third acquisition module to achieve real-time monitoring of the demagnetization degree, flux linkage state, real-time temperature field, and real-time electromagnetic field of each section of the disc motor. The control layer includes a control module for optimizing the control of the disc motor under monitoring based on the demagnetization degree, flux linkage state, real-time temperature field, and real-time electromagnetic field of each section.

[0112] In this way, through the hierarchical design of the data acquisition layer, the integrated monitoring layer, and the control layer, the temperature, demagnetization, and local faults of the permanent magnet zone can be accurately perceived. At the same time, the operation control strategy of the control layer is dynamically optimized based on the monitoring results of the integrated monitoring layer, so as to complete the zone compensation, thermal safety and efficiency coordination, fault-tolerant control, and improve the reliability, efficiency and dynamic performance of motor operation.

[0113] It should be noted that the control layer can optimize the control of the monitored disc motor, change the operating state of the monitored disc motor, and thus change the voltage, current and other data collected in real time by the data acquisition layer. The changed data is then transmitted to the fusion monitoring layer for further monitoring, forming a continuous "monitoring-analysis-control-feedback" closed loop, realizing dynamic intelligent optimization of motor operation.

[0114] Combination Figure 3 As shown, the present invention provides a device 300 for controlling a disc motor, including a processor 301 and a memory 302. Optionally, the device may further include a communication interface 303 and a bus 304. The processor 301, communication interface 303, and memory 302 can communicate with each other via the bus 304. The communication interface 303 can be used for information transmission. The processor 301 can call logical instructions in the memory 302 to execute the above-mentioned... Figure 1 The method shown is for controlling a disc motor.

[0115] Furthermore, the logic instructions in the aforementioned memory 302 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium.

[0116] The memory 302, as a storage medium, can be used to store software programs and computer-executable programs, such as the program instructions / modules corresponding to the method in this invention. The processor 301 executes functional applications and data processing by running the program instructions / modules stored in the memory 302, thus achieving the above-mentioned functionality. Figure 1 The method shown is for controlling a disc motor.

[0117] The memory 302 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the terminal device. Furthermore, the memory 302 may include high-speed random access memory and may also include non-volatile memory.

[0118] This invention provides an electronic device, comprising: an electronic device body; and Figure 2 or Figure 3 The device shown is for controlling a disc motor.

[0119] The present invention provides a storage medium storing computer-executable instructions configured to perform the above-described method for controlling a disc motor.

[0120] The aforementioned storage media can be either transient computer-readable storage media or non-transitory computer-readable storage media. Non-transitory storage media include various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks, and can also be transient storage media.

[0121] The foregoing description and accompanying drawings fully illustrate embodiments of this disclosure to enable those skilled in the art to practice them. Other embodiments may include structural, logical, electrical, procedural, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. Moreover, the terminology used in this invention is for descriptive purposes only and is not intended to limit the claims. As used in the description of the embodiments and claims, the singular forms “a,” “an,” and “the” are intended to equally include the plural forms unless the context clearly indicates otherwise. Similarly, the term “and / or,” as used herein, refers to any and all possible combinations of one or more of the associated listed elements. Additionally, when used in this invention, the term "comprise" and its variations "comprises" and / or "comprising" refer to the presence of stated features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof. Without further limitations, an element defined by the phrase "comprising a..." does not exclude the presence of other identical elements in the process, method, or apparatus that includes said element. In this document, each embodiment may focus on the differences from other embodiments, and similar or identical parts between embodiments can be referred to mutually. For methods, products, etc., disclosed in the embodiments, if they correspond to the method section disclosed in the embodiments, the relevant parts can be referred to the description of the method section.

[0122] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the invention. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0123] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of the systems, methods, and computer program products according to the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing the specified logical function. In some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, or they may sometimes be executed in reverse order, depending on the functions involved. In the descriptions corresponding to the flowcharts and block diagrams in the accompanying drawings, the operations or steps corresponding to different blocks may also occur in a different order than those disclosed in the description; sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps may actually be executed substantially in parallel, or they may sometimes be executed in reverse order, depending on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

Claims

1. A method for controlling a disc motor, characterized in that, include: Acquire the current and voltage information of the stator windings of the disc motor under monitoring during operation; Obtain the current response information corresponding to the stator winding; The bus voltage and temperature information of the disc motor to be monitored, as well as the three-phase current of the stator winding, are obtained. The degree of demagnetization of each zone in the disc motor to be monitored is obtained based on the current response information. The flux linkage state of the permanent magnets in each section of the disc motor to be monitored is obtained based on the current information and the voltage information. The real-time temperature field and real-time electromagnetic field of each zone in the disc motor to be monitored are obtained based on the bus voltage, temperature information and the three-phase current of the stator winding. The monitored disc motor is controlled based on the degree of demagnetization of each zone, the flux linkage state of the permanent magnets in each zone, the temperature field, and the electromagnetic field.

2. The method according to claim 1, characterized in that, The stator winding is connected to an inverter and a current sensor; acquiring the current response information corresponding to the stator winding includes: When the disc motor under monitoring is running, a preset excitation signal is input to the stator winding through the inverter; then the current sensor collects the response current output by the stator winding in response to the excitation signal. The response current is determined as the current response information.

3. The method according to claim 1, characterized in that, The step of obtaining the demagnetization degree of each zone in the disc motor to be monitored based on the current response information includes: The current response information is decomposed using wavelet packet decomposition to obtain several decomposed response components; High-frequency response components are obtained from each of the decomposed response components; The high-frequency response component is input into a preset inductance feature extraction model to obtain the direct-axis inductance feature data corresponding to each partition of the permanent magnet. Based on the direct-axis inductance data, the degree of demagnetization of each zone is determined.

4. The method according to claim 3, characterized in that, The determination of the demagnetization degree of each partition based on the direct-axis inductance data includes: A search operation is performed using a preset inductor demagnetization database to obtain the degree of demagnetization of each partition and the inductance range corresponding to the degree of demagnetization; For each partition, determine the inductance range of its corresponding direct-axis inductance characteristic data; and determine the degree of demagnetization corresponding to the inductance range as the degree of demagnetization of that partition.

5. The method according to claim 1, characterized in that, The step of obtaining the flux linkage state of the permanent magnets in each section of the disc motor to be monitored based on the current information and the voltage information includes: Extract the fundamental current and low-order harmonics of the current signal; extract the fundamental voltage and low-order harmonics of the voltage signal. The back electromotive force time-domain waveform of the disc motor to be monitored is obtained based on the fundamental current, the lower harmonic current, the fundamental voltage, and the lower harmonic voltage. Extract the distortion features corresponding to the time-domain waveform of the back electromotive force; Obtain the waveform data corresponding to the time-domain waveform of the back electromotive force; The waveform data and the distortion features are input into a preset flux linkage feature extraction model to obtain the flux linkage feature values ​​of each partition. The state of each magnetic flux linkage is determined based on its characteristic value.

6. The method according to claim 5, characterized in that, The step of determining the state of each magnetic flux linkage based on its characteristic value includes: The system uses a pre-defined flux linkage state database to perform a lookup operation on each flux linkage feature value to obtain the flux linkage state corresponding to each flux linkage feature value. The pre-defined flux linkage state database stores the correspondence between each flux linkage feature value and each flux linkage state. The flux linkage state corresponding to each flux linkage characteristic value is determined as the flux linkage state of the permanent magnet in each partition.

7. The method according to claim 1, characterized in that, The step of obtaining the real-time temperature field and real-time electromagnetic field of each zone in the disc motor under monitoring based on the bus voltage, temperature information, and the three-phase current of the stator winding includes: Construct a digital twin model of the disc motor to be monitored; The bus voltage, temperature information, and three-phase current of the stator winding are input into the digital twin model of the motor to obtain a simulation model of the candidate motor. The candidate motor simulation model is corrected in real time based on the current information and the voltage information to obtain the motor simulation model. Obtain the simulated temperature field and simulated electromagnetic field of each partition in the motor simulation model; The simulated temperature field of each partition is determined as the real-time temperature field of each partition; the simulated electromagnetic field of each partition is determined as the real-time electromagnetic field of each partition.

8. The method according to claim 1, characterized in that, The control of the disc motor under monitoring based on the demagnetization degree of each zone, the flux linkage state of the permanent magnets in each zone, the temperature field, and the electromagnetic field includes: Magnetic field compensation is performed based on the degree of demagnetization of each zone; Adjust the operating point and current distribution of the monitored disc motor according to the temperature field; The demagnetization trend of the permanent magnets in each partition is determined based on the degree of demagnetization of the partition, the flux linkage state of the permanent magnets in each partition, the real-time temperature field, and the real-time electromagnetic field. When the demagnetization trend indicates an accelerated demagnetization trend, the monitored disc motor is switched to a preset conservative control mode.

9. The method according to claim 8, characterized in that, The magnetic field compensation based on the demagnetization degree of each partition includes: The partitions that need compensation are located based on the degree of demagnetization of each partition; The compensation harmonic current is determined based on the zone that needs compensation and the degree of demagnetization of the zone. Injecting a compensating harmonic current into the stator winding corresponding to the section requiring compensation in order to perform magnetic field compensation for that section.

10. The method according to claim 9, characterized in that, The determination of the compensation harmonic current based on the partition requiring compensation and the degree of demagnetization of the partition requiring compensation includes: In the preset current parameter database, a search operation is performed on the zone to be compensated and the degree of demagnetization of the zone to be compensated to obtain the phase parameters and amplitude parameters of the compensated harmonic current; the current parameter database stores the correspondence between the zone, the degree of demagnetization, and the phase parameters and amplitude parameters. Based on the phase and amplitude parameters, the current is determined to be the compensation harmonic current; the compensation harmonic current is a sinusoidal current.

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